Clinical usefulness of bisphosphonates in oncology: Treatment of bone metastases, antitumoral activity and effect on bone resorption markers

The present article overviews the role of bisphosphonates for the treatment and prevention of bone metastases and their antiangiogenic effects and antitumoral activity. The skeleton is a frequent and clinically relevant site of metastasis in cancer patients. The major events related to bone metastases include bone pain, bone loss, hypercalcemia, spinal cord compression, and fractures. On the basis of their radiographic features, bone metastases are classified as osteoblastic, osteoclastic, or mixed. The primary goals of treatment of bone metastases are reduction of the risk of pathological fractures and other skeletal-related events, and pain control. Bisphosphonates are used to prevent pathological fractures by inhibition of osteoclasts. Recent studies suggest that bisphosphonates have some direct antitumoral activity, mainly mediated through the blockade of angiogenic pathways. Further clinical studies are needed to determine the optimal treatment duration, timing and schedule of bisphosphonates, assess their role as adjuvant therapy for the prevention of bone metastases, and establish their antiangiogenic activity in association with standard cytotoxic and hormonal drugs for treatment of patients with advanced disease.